To David Thompson—who died blind, penniless, and bypassed by history—we owe our first knowledge of the American continent’s rugged Northwest

After Thompson retired from the fur trade, he tried on a number of occasions to have his map published, but never succeeded. He settled in eastern Canada with his half-breed wife and their children, and continued as a surveyor. From 1817 to 1827, he was employed by the British Boundary Commission to survey the international border between Canada and the United States from St. Regis on the St. Lawrence River to the Lake of the Woods, north of Minnesota. Later, he was overcome by a series of misfortunes. Most of his savings disappeared in the unprofitable business ventures of his sons. His eyesight failed. Further difficulties forced him to sell his scientific instruments—and at one time even pawn his coat—in order to eat. When the North West and Hudson’s Bay companies merged, a new generation of fur men forgot the name and achievements of David Thompson, the Nor’Wester.

Thompson’s own modest character contributed to his obscurity. Quiet and unobtrusive, he failed to push himself forward or seek recognition. In extreme poverty, on the edge of complete blindness, he managed when more than seventy years old to write a narrative of his explorations, hoping to make a little money from its sale, in some way Washington Irving heard of it and tried to buy it but, according to Thompson’s daughter, failed to offer enough money or to satisfy Thompson with regard to acknowledgment of its authorship. There were no other bidders. The narrative, like the great map, remained unpublished, and when Thompson died at eighty-seven, there was sparse evidence for historians to know that he had ever existed.

Thompson was active in the Canadian fur trade during some of its most colorful and exciting days, when agents of the rival trading companies were leapfrogging past each other westward across the unexplored forests and plains of the continent, competing with guns and alcohol for the beaver trade of newly discovered tribes. Thompson was born on April 30, 1770, in Westminster, England, of poor and obscure parents, and after his father’s death he received some education at the Grey Coat School, a charitable institution in London. An industrious youth with ability in mathematics and writing, he was bound to the Hudson’s Bay Company as a seven-year apprentice, at the age of fourteen. Young Thompson was shipped to the bleak and lonely Churchill Factory post on Hudson Bay, and after a year was sent on foot with two Indian guides to York Factory, 150 miles away. He had a gun, but was given no provisions for the trip, and the difficult journey along the icy, windswept shore of the bay taught the fifteen-year-old boy how to live off the land.

His wilderness education continued at York Factory, where he served as a clerk and hunter; one year later, in 1786, he was sent with an expedition deep into central Canada to establish a new trading post on the south branch of the Saskatchewan River, about as far west as white men had yet penetrated. Though only sixteen, and a quiet, unassuming youth with a devoutly religious turn of mind, he was already considered an unusually capable wilderness man, bold, intelligent, and resourceful, a reliable leader with a sense of responsibility to his companions and a devotion to hard work and duty. The next year he was selected to accompany six men southwestward across the unexplored buffalo plains to find the Blackfeet Indians, teach them to trap beaver, and turn them into providers of furs for the Hudson’s Bay Company.

Near present-day Calgary, Alberta, the group found the Blackleet, and Thompson spent the winter in the lodge of a friendly and aged chief who instructed him in the life and traditions of the Indians inhabiting the country along the eastern side of the Rockies. Much of what Thompson learned that winter, and recorded in his narrative, is the only known account of Indian history in that area before the white man came.

Back on the Saskatchewan River, Thompson became interested in meteorology and surveying, and was instructed by Philip Turnor, the official surveyor of the Hudson’s Bay Company. He kept daily records of weather, temperature, and wind, and began to take astronomical readings and learn to solve problems of time, latitude, longitude, and variations of the compass. He acquired a ten-inch brass sextant and, wherever he traveled, made careful observations with compass, watch, and a crude artificial mercury horizon. His thoroughness and skill gradually helped him attain a high degree of precision in his calculations, and Dr. Tyrrell was only the first among many geographers and surveyors who, retracing the ground with modern instruments in later years, were surprised by the accuracy of Thompson’s work.

In 1791 his apprenticeship ended, and the following year he became a trader. For a number of years he was assigned to the great watery wilderness west of Hudson Bay. He traveled through thick forests sown with lakes, streams, and mosquito-filled bogs, and across treeless muskeg, stretching in cold and lonely silence toward the Arctic horizon. No white man had been in the country before him, and wherever he went, he surveyed and mapped. He built log huts in the forested areas for the trade of small, isolated groups of Indians, explored canoe routes through muddy, marsh-choked ends of lakes, and charted difficult portages around rushing waterfalls and boulder-strewn white water.